Hole saw assembly

ABSTRACT

A hole saw assembly is revealed. The hole saw assembly is a hole saw with a quick change drill rod. The hole saw assembly includes a quick release device and the drill rod, both arranged at the hole saw. The drill rod is inserted through the quick release device and the quick release device is for fastening and releasing a drill head of the drill rod. Thereby the drill rod is fitted over the quick release device and users can fasten and release the drill rod quickly. Users can also quickly mount a shank of the drill rod quickly into the hole saw. The drill rod is fast slid out of the quick release device for replacement of a new drill rod. Then the shank is locked on the hole saw so that the shank and the hole saw can rotate synchronously.

NOTICE OF COPYRIGHT

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to any reproduction by anyone of the patent disclosure, as itappears in the United States Patent and Trademark Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

The present invention relates to a hole saw assembly, especially to ahole saw assembly that includes a drill rod able to be mounted in andreleased from a hole saw quickly. The drill rod is generally fixed in anaxial hole of the hole saw and is applied to hole saws with differentdiameters used as a shaft for positioning. Thus the hole saw will nothave offset during rotation.

2. Description of Related Arts

In a conventional hole saw assembly, a drill rod can be quickly changedfrom the hole saw by a quick release device. The design of most of thequick release devices is for hole saws with larger diameter (such ashole saws with the diameter larger than 30 mm) For example, refer toU.S. Pat. No. 8,328,474, a quick change arbor, a hole cutter and amethod suitable for hole saws with high torsion and large diameter arerevealed. A hole cutter 12 includes an end plate 14. A drive shank 24includes a body portion 26 with flats 25. The flats 25 are fastened onthe end plate 14 while the pilot bit 64 is arranged at the drive shank24. The body portion 26 is assembled with a collar 50 to form the quickchange pilot bit 64. The quick change device is connected to the driveshank 24 and is having drive pins 36 set on the end plate 14 and driveninto the corresponding drive pin apertures 18. The hole cutter 12 usesthe drive shank 24 as a main transmission shaft. However, such structureis unable to be applied to hole saws with diameter smaller than 30 mm.This is due to that the width of the contact surface of the hole sawswith the diameter smaller than 30 mm is unable to be assembled with thedrive pins 36.

Refer to Canadian Pat. No. 2283453, an extractor is revealed. Theextractor is applied to hole saws with small diameter. An adaptor isaxially movable along a drill rod so as to remove debris attached on ahole saw and the drill rod. The drill rod is unable to be released fromthe adaptor. When the drill rod gets damaged, the drill rod and theadaptor should be replaced together. The adaptor is axially moved andthen a head part of the drill rod is positioned by radial rotation. Theadaptor is against and locked by a spring.

After being used for a period of time, the spring may undergo elasticfatigue and the adaptor is unable to be locked and positioned on theposition required. This results in that the head part of the drill rodis unable to be positioned and moved axially. This is dangerous for theusers during the operation because the head part may be biased and getbroken. Thus the drill rod is unable to be used as a positioning shaftof the hole saw.

For overcoming shortcomings of the conventional devices, reducing offsetof the drill rod and quick change of the drill head from the hole saw,there is a need to provide a novel hole saw assembly that includes aquick release device designed for hole saws with diameter no more than30 mm.

SUMMARY OF THE PRESENT INVENTION

Therefore it is a primary object of the present invention to provide ahole saw assembly with a quick change drill rod that includes a holesaw, a quick release device and a drill rod. The quick release deviceand the drill rod are disposed on the hole saw. The diameter of the holesaw is no more than 30 mm. The hole saw consists of an end surface andan opening. The opening is circular and the end surface is arranged witha threaded hole. The drill rod including a drill head and a shank isassembled with the quick release device. The shank is extended to formthe drill head and a circular groove is disposed on the shank.

The quick release device is composed of a ring, a sleeve and a drivebody. The ring is composed of a first end and a second end. The firstend has a flange while the second end has a hexagonal hole. The sleevehas an extension portion that is extended to form a first connectionportion. The sleeve also includes an axial hole that is extended axiallyfrom the extension portion to the first connection portion. The drivebody includes a second connection portion. The second connection portionis axially extended to form a stopping portion while the stoppingportion is extended axially to form a hexagonal portion. The axialextension of the hexagonal portion forms a threaded portion. The drivebody further includes an assembly hole that is axially extended from thesecond connection portion to the threaded portion. The second connectionportion is arranged with at least one socket and a spring is fitted overthe hexagonal portion.

The second connection portion is mounted into the first connectionportion and the stopping portion is against the edge of the firstconnection portion. The sleeve is assembled with the drive body firstand then is mounted into the ring. The threaded portion is extended fromthe ring and the flange of the ring is around the extension portion ofthe sleeve. Thereby the quick release device is formed.

The quick release device is threaded into the hole saw and the drill rod5 is directly slid into and assembled with the quick release device. Thequick release device has a structure for releasing and locking the drillhead. Thereby the drill rod is fitted into the quick release device andusers can fasten and release the drill rod quickly. Users can alsoquickly mount the shank quickly into the hole saw. The drill rod is fastslid out of the quick release device for replacement of a new drill rod.Then the shank is locked on the hole saw so as to be rotatedsynchronously with the hole saw.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is an explosive view of an embodiment according to the presentinvention;

FIG. 1-1 is a schematic drawing showing a second end of a ring of anembodiment according to the present invention;

FIG. 2 is an explosive view of a quick release device of an embodimentaccording to the present invention;

FIG. 3 is a perspective view of a quick release device of an embodimentaccording to the present invention;

FIG. 4 is a perspective view of an embodiment according to the presentinvention;

FIG. 5 is a schematic drawing showing an embodiment in use according tothe present invention;

FIG. 6 is another schematic drawing showing an embodiment in useaccording to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer to following embodiments for details, features and effectsof the present invention.

A hole saw assembly of the present invention is a hole saw 6 with aquick change drill rod 5. Refer to FIG. 1, FIG. 2 and FIG. 3, the holesaw assembly includes the hole saw 6, a quick release device A and thedrill rod 5. Both the quick release device A and the drill rod 5 areassembled with the hole saw 6. The hole saw 6 includes an end surfaceand an open end. The open end is a circular opening while the endsurface is disposed with a threaded hole 61. The drill rod 5 isassembled with the quick release device A and is having a drill head 52and a shank 51. The shank 51 is a hexagonal prism and is extendedaxially to form the drill head 52. A circular groove 53 is arranged atthe shank 51.

As shown in FIG. 2, the quick release device A consists of a ring 1, asleeve 4 and a drive body 3. The ring 1 is composed of a mounting hole11, a first end 1 a and a second end 1 b. The mounting hole 11 is acircular hole penetrating the ring 1. The mounting hole 11 is extendedto the second end lb and formed a hexagonal hole 11 a at the second end1 b, as shown in FIG. 1-1. Thereby the second end 1 b forms a stoppingpart 111. The hexagonal hole 11 a is a bit smaller than the mountinghole 11 so that the second end 1 b becomes the stopping part 111. Thefirst end 1 a has a flange 12. The sleeve 4 has an axial hole 41, anextension portion 42, and a first connection portion 43. The extensionportion 42 is extended to form the first connection portion 43 while theaxial hole 41 is extended axially from the extension portion 42 to thefirst connection portion 43. The drive body 3 includes an assembly hole31, a second connection portion 32, a stopping portion 33, a hexagonalportion 34 and a threaded portion 35. The stopping portion 33 is formedby axial extension of the second connection portion 32 while thestopping portion 33 is extended axially to form the hexagonal portion 34and the hexagonal portion 34 is extended axially to form the threadedportion 35. The assembly hole 31 is hexagonal and is axially extendedfrom the second connection portion 32 to the threaded portion 35,penetrating the drive body 3.

The second connection portion 32 is disposed with at least one socket321 a, 321 b. Each of the sockets 321 a, 321 b needs to fit a bead 36 a,36 b. A spring 2 is fitted over the hexagonal portion 34 and the secondconnection portion 32 is mounted into the axial hole 41 of the firstconnection portion 43. The stopping portion 33 is against the edge ofthe first connection portion 43.

The sleeve 4 is assembled with the drive body 3 first and then ismounted into the mounting hole 11 of the ring 1. The extension portion42 is against the edge of the first end 1 a. The threaded portion 35 isextended from the second end 1 b of the ring 1 while the hexagonalportion 34 is fitted in the hexagonal hole 11 a of the ring 1. Theflange 12 of the ring 1 is around the outer diameter of the extensionportion 42 of the sleeve 4. Thus the ring 1 can be axially moved withina certain distance around the outer diameter of the drive body 3 andturned back to the original position. Therefore the assembly of thequick release device A is completed.

As shown on FIG. 4, the threaded portion 35 of the quick release deviceA is engaged with the threaded hole 61 of the hole saw 6 and the drillrod 5 is directly slid into and assembled with the quick release deviceA so as to form the hole saw assembly. The drill rod 5 can be fastenedor released by the quick release device A. The drill rod 5 is mountedinto the quick release device A so that users can fasten and release thedrill rod 5 quickly. The user can quickly assemble the shank 51 on thehole saw 6. The shank 51 of the drill rod 5 can be slide out of thequick release device A for replacement of a new drill rod 51. Then theshank 51 of the new drill rod 51 is fastened on the hole saw 6 by thequick release device A so that the shank 51 can rotate with the hole saw6 synchronously.

As shown in FIG. 5 and FIG. 6, first the threaded portion 35 of thequick release device A is fastened in the threaded hole 61 of the holesaw 6 a. Then the ring 1 of the quick release device A is axiallyremoved within a certain distance. Thereby the edge of the firstconnection portion 43 of the sleeve 4 is away from the sockets 321 a,321 b. Now the beads 36 a, 36 b in the sockets 321 a, 321 b respectivelyare no more pressed by the first connection portion 43 and are moveable.Then the shank 51 of the drill rod 5 is inserted into the assembly hole31 of the quick release device A, slid through the threaded portion 35and penetrated the hole saw 6. The ring 1 is not released until thecircular groove 53 of the shank 51 is moved to the position of thesockets 321 a, 321 b. Next the ring 1 is turned back due to the spring2. At the same time, the sleeve 4 is also turned back due to the ring 1.Now the inner surface of the first connection portion 43 of the sleeve 4presses the beads 36 a, 36 b so that the beads 36 a, 36 b are stoppedand fixed in the sockets 321 a, 321 b and against the circular groove 53of the shank 51 respectively. Thereby the shank 51 is locked andfastened in the quick release device A. Refer to FIG. 5, one end of theshank 51 is extended from the quick release device A and is used as atransmission shaft of the hole saw 6 assembly. Moreover, the ring of thequick release device A is moved axially within a certain distance againwhen the drill rod 5 is quickly slid out of the quick release device A.The edge of the first connection portion 43 of the sleeve 4 is away fromthe sockets 321 a, 321 b. As shown in FIG. 6, without being pressed bythe first connection portion 43, the beads 36 a, 36 b in the sockets 321a, 321 b respectively are moveable. Thus the circular groove 53 of theshank 51 is no more locked and fastened by the beads 36 a, 36 b. Theshank of the drill rod can be slid out of the quick release device A andreleased from the hole saw 5. The ring 1 is not released and not turnedback until the drill rod 5 is completely released.

The present invention has following advantages:

1. First of all, the drill rod 5 is directly inserted through the quickrelease device A while the quick release device A is directly assembledwith the hole saw 6. The shank 51 of the drill rod 5 is a transmissionshaft of the hole saw 6. After being connected to electric tools, theshank 51 is driven to rotate by the electric tools and the drill head 52is synchronously driven to rotate by the shank 51. Thus offset caused byvibration during high-speed rotation can be avoided.

2. Secondly, the quick release device A of the present invention withsimple structure is directly engaged and integrated with the hole saw 6to form an integrate assembly. Thereby the drill rod 5 can be directlyslid into the assembly of the quick release device A with the hole saw6. Once the user wants to remove the drill rod 5 from the hole saw 6, heonly needs to move the ring 1 axially within a certain distance. Thusthe drill rod 5 is released from the hole saw 6 quickly.

3. The assembly hole 31 of the drive body 3 is hexagonal. The shape ofthe assembly hole 31 matches that of the shank 51 of the drive rod 5 sothat the shank 51 can be mounted into the assembly hole 31. Thehexagonal portion 34 of the drive body 3 is fitted into the hexagonalhole 11 a of the ring 1 so that the drill rod 5 can be positioned duringthe rotation and idle rotation can be avoided. Moreover, the drive body3 is moved axially, but not radially within the hexagonal hole 11 a ofthe ring 1. In other words, the ring is moved along the drive body 3.

It should be noted that the quick release device A of the presentinvention is a component of the hole saw 6 and used for quickreplacement and fastening of the drill rod 5. The assembly of thepresent invention is suitable for hole saws whose diameter is no morethan 30 mm.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details, and representative devices shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. A hole saw assembly with diameter no more than 30mm, comprising: a hole saw, a quick release device and a drill rod,wherein the quick release device is disposed on the hole saw and thedrill rod is directly slid into the quick release device so as to formthe hole saw assembly; wherein the quick release device further includesa ring, a sleeve and a drive body, wherein the ring is arranged with amounting hole, a first end and a second end, wherein the mounting holeis a circular hole penetrating the ring, wherein the first end has aflange while the second end has a hexagonal hole, wherein the sleeveincludes an extension portion, a first connection portion formed byextension of the extension portion and an axial hole that extendsaxially from the extension portion to the first connection portion,wherein the drive body includes a second connection portion, a stoppingportion formed by axial extension of the second connection portion, ahexagonal portion formed by axial extension of the stopping portion, athreaded portion formed by axial extension of the hexagonal portion, anda hexagonal assembly hole axially extended from the second connectionportion to the threaded portion, wherein the second connection portionis disposed with at least one socket and the socket is mounted with abead, wherein a spring is fitted over the hexagonal portion, the secondconnection portion is mounted into the axial hole of the firstconnection portion and the stopping portion is against an edge of thefirst connection portion, wherein the sleeve is assembled with the drivebody first and then mounted into the mounting hole of the ring, whereinthe extension portion is against an edge of the first end and thethreaded portion is extended from the second end of the ring while thehexagonal portion is fitted in the hexagonal hole of the ring, whereinthe flange of the ring is around an outer diameter of the extensionportion of the sleeve and the ring is able to be axially moved within acertain distance around an outer diameter of the drive body and turnedback to original position.
 2. A hole saw assembly, as claimed in claim1, wherein the hole saw is arranged with a threaded hole for beingengaged with the threaded portion of the quick release device.3. Thepruning shears, as claimed in claim 2, wherein the first brake arm isdisposed with a first axial part and a second axial part.
 3. hole sawassembly, as claimed in claim 1, wherein the drill rod further includesa drill head and a shank, wherein the shank is a hexagonal prism and isextended axially to form the drill head, wherein a circular groove isarranged at the shank so that the bead of the quick release device isfastened in the circular groove.
 4. A hole saw assembly, comprising: ahole saw having an opening and an end surface, wherein the diameter ofthe hole saw is no more than 30 mm, wherein the end surface is disposedwith a threaded hole for being engaged with a threaded portion of aquick release device; a drill rod having a drill head and a shank,wherein the shank is a hexagonal prism and is extended axially to formthe drill head, wherein a circular groove is set on the shank, wherein abead of the quick release device is fixed in the circular groove whenthe drill head is slid into the quick release device, wherein one end ofthe drill rod is extended from the quick release device and is used as atransmission shaft of the hole saw assembly; a quick release device thatincluding a ring, a sleeve and a drive body, wherein the ring isarranged with a mounting hole, a first end and a second end, wherein themounting hole is a circular hole penetrating the ring, wherein the firstend has a flange while the second end has a hexagonal hole, wherein thesleeve further includes an extension portion, a first connection portionformed by extension of the extension portion, and an axial hole thatextends axially from the extension portion to the first connectionportion, wherein the drive body further includes a second connectionportion, a stopping portion formed by axial extension of the secondconnection portion, a hexagonal portion formed by axial extension of thestopping portion, a threaded portion formed by axial extension of thehexagonal portion, and a hexagonal assembly hole axially extended fromthe second connection portion to the threaded portion, wherein thesecond connection portion is disposed with at least one socket and thesocket is mounted with a bead, wherein a spring is fitted over thehexagonal portion, wherein the second connection portion is mounted intothe axial hole of the first connection portion and the stopping portionis against an edge of the first connection portion, wherein the sleeveis assembled with the drive body first and then is mounted into themounting hole of the ring, wherein the extension portion is against anedge of the first end and the threaded portion is extended from thesecond end of the ring while the hexagonal portion is fitted in thehexagonal hole of the ring, wherein the flange of the ring is around anouter diameter of the extension portion of the sleeve and the ring isable to be axially moved within a certain distance around an outerdiameter of the drive body and turned back to original position.
 5. Thehole saw assembly, as claimed in claim 1, wherein fastening andreleasing of the drill rod further comprises the steps of: first axiallymoving the ring of the quick release device within a certain distance sothat an edge of the first connection portion of the sleeve is away fromthe socket and the bead in the socket becomes moveable, thus the shankof the drill rod being able to be inserted into the assembly hole of thequick release device; sliding through the threaded portion and extendedfrom the hole saw, wherein the ring is not released until the circulargroove of the shank is moved to the position of the socket, and then thering is turned back due to the spring and the sleeve is also turned backdue to the ring, wherein an inner surface of the first connectionportion of the sleeve presses the bead so that the bead is stopped andfixed in the socket and against the circular groove of the shank,thereby the shank is locked and fastened in the quick release device;axially moving the ring of the quick release device within a certaindistance again when the drill rod is quickly slid out of the quickrelease device, thus the edge of the first connection portion of thesleeve being away from the socket and the bead in the socket becomesmoveable, wherein the circular groove of the shank is no more locked andfastened by the bead and the drill rod is able to slide out of the quickrelease device and release from the hole saw, wherein the ring is notreleased until the drill rod is released completely.